1. Field of Art
The present disclosure relates generally to suction and discharge valves for reciprocating pumps. More particularly, the present disclosure relates to apparatus and methods that enable access to suction and discharge valves of reciprocating pumps and closure of chambers which contain them.
2. Description of the Related Art
Reciprocating pumps are used in various operations to pressurize an often abrasive slurry mixture of solids and liquids. For example, reciprocating pumps are used in drilling operations to pressurize a slurry mixture of solids and liquids known as drilling mud, which is then conveyed to the bottom of a borehole drilled in the earth. The pressurized mud is used to maintain appropriate borehole pressure, lubricate and cool a downhole drill bit, and carry loosened sediment and rock cuttings from the borehole bottom to the surface. At the surface, the cuttings and sediment are removed from the returning drilling mud, and the filtered drilling mud may be recycled and pumped back to the borehole bottom.
Suction and discharge valves are used in reciprocating pumps to control the flow of fluid into and out of the pump's cylinders where the fluid is pressurized. Due to the highly abrasive nature of the particles often present in the fluid to be pressurized, the valves and seals of the pumps must be designed to resist harsh abrasion, while maintaining positive sealing action under relatively high operating pressures. Even so, the valves have a finite service life, and normally fail due to deterioration of the elastomeric sealing element of the valve, deterioration caused by erosion of the mating metal contact surfaces of the valve and valve seat, or combinations thereof. When leakage through the valves is sufficient to render the pump unable to maintain satisfactory fluid pressure for the drilling conditions, the valves must be replaced.
Maintenance of these valves is a time consuming and difficult process that presents risks of injuries to service personnel. To service most conventional valves, the valve cover is typically removed by first loosening the valve cover with a heavy sledge hammer, and then unscrewing the valve cover to disengage a relatively long length of threads between the cover and its seat. Further, maintenance of most conventional valves is usually costly since the pump must be shut down during such maintenance procedures, thereby interrupting the drilling activity.
Accordingly, there remains a need to develop apparatus and methods for safely and quickly accessing suction and discharge valves of reciprocating pumps.